The SamClock
RINGER, constitutes natural extension of digital clockSamClock. With this circuit we acquire a programmed
exit ringer or excitation of external units, via the RL1. The programming does not remain
classically, in order that make most clock, in the hour and in minutes, but advance and in
the seconds, acquiring thus bigger precision, where they are this desirable. And in this
circuit is maintained the philosophy of distinguishable materials, acquiring thus the
possibility, of adding or of removing possibilities, adapting him, in the needs that we
have, as in the basic unit. Thus what it does not need exit of seconds, relay or buzzer,
it very well can him pass and suppress the proportional unit..

How it
works?

The control becomes,
connecting the entries of IC1-6 [ 4511 ], with the entries of IC1-6 [ 4028 ] of basic
unit, as it appears and in the circuit. The exits of IC1-6 [ 4028-BCD to decimal decoder ]
they are connected in switches DIL. In each switch correspond also a number from 0 until
the 9, as it appears in the numbers, that are found except frame of switches. When the
switch is closed [ ON ], then the logic level of exit that his correspond it is
transmitted in the corresponding gate, that follow. If we want , to have excitation of
circuit in time 12: 05 ': 46 ", we close switch S7 [ON ], in order to is supplied the
circuit with voltage and places switches DIL, in the places: S1[1 ], S2[2 ], S3[0 ], S4[5
], S6[6 ]. When the time reache and the DISPLAY they show the above hour then we will have
logic high level [ H ] in the corresponding exits of the IC1-6, as it appears in the below
table.

HOURS

MINUTES

SECONDS

Display

1

2

0

5

4

6

Out pin

IC1/14

IC2/2

IC3/3

IC4/6

IC5/4

IC6/7

Switch

S1/1

S2/2

S3/0

S4/5

S5/4

S6/6

All the
exits become [ H ] and the exit of IC8b, become [ H ], for 1sec, drive the Q1 that is
conductible leading the entry IC8c/9, to the ground. His situation change also exit of
IC8c/10, from [ L ] become and remain [ H ], it leads Q 1-3, that turn on: the LD1 turns
on, buzzer sound, also relay RL1 close, driving certain external unit. When that exit of
IC8b becomes [ H] for 1 second and afterward become [ L ], this is enough in order to
excite the IC8c and IC8d and it change situation. If we open the switch S7 [ OFF ], then
ringer closed, the LD1 is turn off, the RL1 open, the buzzer stop it sound, waiting for
the next circle. If we close again the S1, we have excitation reason of C3. With the TR1
we regulate the level of ringing. the supply of circuit it become from the supply of basic
clock, the consumption it depend from the relay that we will use.

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